Chain wrench.



A. M. TILTON.

CHAIN WRENCH.

APPLICATION FILED JUNE 21, 1907.

Patented Oct. 27, 1908.

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ALBRO M. TILTON, OF BROOKLYN, NEW YORK.

CHAIN WRENCH.

Specification of Letters Patent.

Patented Oct. $27, 1 908.

Application led June 21, 1907. Serial N o. 380,056.

To all whom it may concern:

Be it known that I, ALBRo M. TIL'roN, citizen of the United States of America, and resident of 553A Monroe street, Brooklyn, New York, have invented certain new and useful Improvements in Chain Wrenches, of which the following is a speciiication.

My invention relates to chain pipe wrenches of the duplex or double jaw type. As is well known, the jaws of this class ofi wrench consist of hard steel plates, having serrated edges for gripping the pipe. As now constructed, and, in order to avoid the expense of making the handles of the same material as the jaws, the latter are not made integral with the handle, but are xedly attached to it by bolts passing transversely through the jaws and through the handle. Heretofore, in this class of wrench, the serrations or teeth on the jaws have been perpendicular, or precisely at rightl angles to a plane in which the axis of the handle moves as the latter is turned around the pipe perpendicularly thereto. It is found 1n practice, hcwever, that, when the wrench is held in a position exactly perpendicular to the pipe so that the serrations are parallel thereto, the teeth do not promptly and securely engage, but, on the contrary, are liable to slip over the surface more or less. The operator, to avoid the slippinge'lfect, inclines the wrench slightly to the axis of the pipe in order to bring the corners of the teeth into contact with it since they will engage more readily than their long edges. When thus used, the axis of the handle describes a conical surface instead of a plane, as the pipe is rotated, thereby throwing the strain largely on one jaw, and, furthermore, a Wedgelike effort is exerted on that jaw tending 'to force it away from the handle. This strain falls, of course, on the bolts which secure the jaw to the handle, and it is atonce a bending and a torsional strain. The bolts, not being designed to meet this particular strain, are often broken, and the wrench rendered useless. j

It is of great advantage to have the teeth or serrations of opposite slo e as by this means the wrench jaws are cliecked by the opposition so created in their tendency to swing sidewise on the pipe.

One object of the present invention is to produce a chain wrench, the serrated edges or teeth of which are so constructed as to overcome or avoid the hereinbefore mentioned deficiencies common to this class of wrenches.

By reason of my construction of the teeth or serrations, I get the full power of both jaws on the pipe, and the strain on the jaws, instead of being in a direction away from each other and fromthe handle, is inward or toward the handle. Where' the strain is thus inward it is received by the bearing surfaces of the jaws on the handle, and the bolts are thus relieved of any undue strains. Furthermore, by my construction of the teeth or serrations, I obtain the quick grip here* tofore obtained only by inclining the wrench.

I obtain these ob `ects by causing the teeth or serrations to e inclined, instead of at right angles, to the plane of perpendicular rotation of the wrench around the pipe. The teeth, instead of being parallel to the axis of the pipe, are then at an oblique angle thereto, and a wedgelike action takes place between the two when the wrench is rotated, which causes the pipe to be quickly and securely gripped. At the same time, the full gripping surfaces of the teeth of each jaw come into lay instead of merely the corners of the teeti of one jaw, as when an ordinary chain wrench is tilted in the manner hereinbefore mentioned.

A further object of my invention is to so design the wrench that certain strains heretcfore commonly falling on the jaws, or on the bolts which secure the same to the handle, shall, instead, fall upon the handle by reason of the extended surface over which, inmy wrench, the handle engages the jaws.

Naturally, the more extended the bearing surfaces of the jaws on the handle, the stronger is the wrench. If, however', with the object of enlarging these bearing surfaces, the aws were to be so attached to the handle that the end of the latter would lie between, or opposite the serrated portions of the jaws, then, for certainsizes of pipe, at least, the inner parts of the serrated edges, or those parts opposite the end of the handle, would be ineffective for grip ing. A pipe to be effectively gripped, wit out being distorted, should engage the chain over a considerable surface. lf the end of the handle lies opposite a portion of the gripping edge of the tool and the chain be led in the usual manner over the end of the handle and to the locks on the other side, it will be found that the chain will not sufficiently wrap certain sizes of pipe, that is to say, unless 4the pipe engages the jaws at points outward beyond the end of the handle.

Accordingly, and in order to render all parts of the gripping edges at all times effective, the handle, in wrenches as heretofore constructed, terminates at a oint on the jaws to the rear of the ends o the serrated edges. By terminating the handle in this manner, however, its bearing' surfaces on the jaws are restricted. Furthermore, in such a construction, the jaws form in effect, a continuation of the handle, or, rather, constitute part of the arm or lever through which the turning moment on the pipe is effected. The turning arm or lever, therefore, consists, in part, of the handle, and, in part, of the jaws, and severe strains fall upon the bolts that secure the jaws to the handle and upon the limited bearing surfaces of the jaws on the handle. lf, on the other hand, it were practicable to extend the handle of the tool to a point opposite to or past the point of jaw at which the gripping takes effect, then the handle would in itself form a complete arm or lever extending from the source of power to the pipe, and any strain on the jaws would be largely received by the effective bearing surfaces of the latter on the handle, instead of by the bolts or smaller bearing surfaces, as when the handle terminates to the rear of the serrated edges of the jaws. By extending the handle to, or past, the gripping point, the effort on the jaws and locks resolves itself into a direct pressure on the handle substantially perpendicular thereto, instead of into a turning movement around the end of the handle as heretofore. As before stated, however, an' obstacle to the proper extension of the handle lies in the rendering ineffective for gripping of certain parts of the jaws, because of the position assumed by the chain.

In my wrench, I do extend the handle outward considerably beyond the rear end of the serrated edges of the jaws, and, by so doing, obtain the various advantages enumerated. By bifurcating the end of the handle, however, to provide a passage therethrough for the chain, l enable the chain to take such a position that no matter what the size of pipe operated upon, or at what part of the jaw it is engaged, the chain wraps it over a large part of its circumference, and thus causes it to be effectively gripped. The arms of the fork or bifurcation in the handle of my wrench furnish the same extended bearing for the jaws that would be obtained were the solid handle extended, while the passage for the chain between the arms of the fork allows the chain the freedom that it would have were the handle terminated to the rear of the serrations, as in wrenches heretofore made. It is to be borne in mind, however, that I do not claim to be the first to bifurcate the handle of a wrench for any purpose whatever. U. S. Patents NOS. 499,508, 570,214, 577,553, 577,654 and 818371 and others show chain wrenches having bifurcated handles. In these patents, however, the bifurcation is simply to receive the pivoted link member of the chain, or at the most, as in the case of Patents Nos. 577653 and 577654 to guide a cable chain by permitting the passage therethroughof one side of the vertical link. entire chain does not pass through the bifurcation in any of these patents, and the path of the chains in each is over the end of the bifurcated handle instead of directly through it to the locks. In each of these patents .the handle terminates to the rear of the serrations, as heretofore explained.

Having briefly set forth the objects and nature of my invention, l will now describe the same in detail in connection with the accompanying drawing, in which Figure 1 is a view in sectional elevation on the line 1-1 of Fig. 2 showing the assembled wrench. Fig. 2 is a view in endl elevation of the wrench. Fig. 3 is an eniarged detail view showing in side elevation the teeth or serrations.

Referring to the drawings: the handle 1 is shown as bifurcated at its end to form a yoke between the arms 2 and 3 of which the link i of the chain is pivoted on the bolt 5. Near the end of each of the arms 2 and 3, and on either side thereof are pockets (i, the opposing pockets together forming the chain locks. Referring to Fig. 2, it will be seen that there is a clear passage 7 between the arms 2 and 3 at that point of the handle at which the locks are carried. The jaws consist of steel plates S and 9 having long slots or pockets 10 and 11 in their interior faces, extending from the lower ends 12 of the jaws to a point 13 above the locks. These slots 10 and 1l are of a width to snugly receive and embrace the side walls 14. and 15 of the handle, and are of sufficient depth to permit the locks to be flush with the face of the jaws. The jaws are applied to either side of the handle so that the latter iits within the pockets 10 and 11, and are then secured to the handley by the bolt 5 on which the link i is mounted, and by the bolt 16. The edges of both jaws are serrated on either side as indicated at 17. Referring'to Figs. 2 and 3 it will be noted that the teeth or serrations, instead of being lat right angles to the faces of the aws, are in- The olined thereto. The inclination of the teeth or serrations is in the direction of movement of the wrench when in use. The teeth 17 on the two jaws are shown as oppositely inclined; that is to say, both sets of teeth are inclined upward and toward the center oi the tool. The action of the pipe on aws having teeth inclined in this manner, is to cause the teeth to act as wedges to compress the jaws against the faces of the handle. The teeth also bite the pipe with a vwedge like action so that it is practically impossible for any slipping to take place between the two. Whereas I have shown the teeth 17 as oppositely inclined, yet the wedgelike action of the teeth on the pipe and the quick grip can be obtained if the teeth slant in the same direction on each j aw. lf desired, one face of each jaw may extend slightly beyond the other face, whereby the edges may present a bevel and the teeth be given a compound incline.

lt will be noted that the bearing surfaces of the jaws on the bifurcated handle extend considerably forward of the ends 18 of the serrated edges. The location of the locks 6 at the end oit the handle opposite the passage j 7 allows of a direct pull on the jaws toward the handle. lf the locks were located further down the handle, the pull on them would be in a direction somewhat parallel to, or along, the handle, instead of toward it. This latter pull throws more strain on the locks and bolts, and is less desirable than the direct pull to the handle, shown.

It will be understood that the structure shown in the drawings is capable of certain variations or modifications within the scope of the invention.

l claiml. ln a chain wrench, the handle, the chain, two jaws rigidly attached to the handle, each jaw having a toothed or serrated biting edge, the teeth or serrations of which are oppositely inclined and are obliquely inclined to the plane of movement of the axis of the handle when the latter is rotated around the jaws as a pivot.

2. In a chain wrench, the handle, the chain, two jaws, the handle being between the jaws and rigidly attached thereto, teeth or serrations on ,the biting edge of each of the jaws extending obliquely across the face of the jaws forwardly from and toward the axial line of the handle.

3. ln a chain wrench, the handle, the chain, two jaws rigidly attached to the handle, each jaw having a toothed or serrated edge, the teeth or serrations of which extend obliquely across the faces of the edges and in opposite directions on the two jaws.

4. In a chain wrench, a handle, a chair, two serrated jaws and chain locks on the side of the handle opposite the jaws, the handle extending appreciably outward of the rear ends ofthe serrated portions ofthe jaws, and having therethrough in proximity to the aws a passage of a size and shape to permit the body of the chain, after it has been led around the ipe or other object, to pass through the liandle in an approximately direct line to the locks on the opposite side.

5. In a chain wrench, a handle, a chain, two serrated jaws mounted at the end of the handle and chain locks on the side of the handle opposite the jaws, the handle extending appreciably outward of the rear ends of the serrated portions ofthe jaws, and having therethrough in proximity to the jaws a passage of a size and shape to permit the body of the chain, after it has been led around the pipe or other obj eet, to pass through the handle in an approximately direct line to the locks on the opposite side.

6. In a chain wrench, a handle, a chain, two serrated jaws and chain locks on the side of the handle opposite the jaws, the handle extending appreciably outward of the rear ends of the serrated portions of the jaws, and being forked to provide a passage of a size and shape to permit the body of the chain, after it has been led around the pipe or other object, to pass through the handle in an approximately direct line to the locks on the opposite side. j

7. In a chain wrench, a handle, a chain, two serrated jaws and chain locks carried by the handle on the side ofthe handle opposite the jaws, the handle extending appreciably outward of the rear ends ol the serrated portions of the jaws, and having therethrough in proximity to the jaws a passage of a size and shape to permit the body of the chain, after it has been led around the pipe or other object, to pass through the handle in an approximately direct line to the locks on the opposite side.

8. ln a chain wrench, a handle, the jaw, and a chain lock, the handle being forked to provide therethrough from side to side a passage of a size and shape to admit the body of the chain, after the latter has been passed around the pipe or other object.

9. In a chain wrench, a handle, the jaw, and a chain lock, the handle having therethrough from side to side a passage of a size and shape to admit the body of the chain after the latter has been passed around the pipe or other object and the loclr` being so situated with respect to the passage that the chain when engaging the locks exerts a strain on the latter in a direction toward the handle pd substantially at right angles to the han- 10. In a chain wrench, a handle, a jaw, a chain attached to the handle below the jaw, a chain lock, the handle having therethrough from side to side above the point of attaehacross the face of each jaw in a direction out- 10 ment of the chain a passage of a size and ward and downward toward the handle. sha e to admit the body of the Chain after Signed by me at Manhattan, N. Y. City thel attwr has been passed around the pipe or I this 6th day of June, 1907. ot er o Jeet.

1l. ln a Chain wrench, the handle, the ALBRO M' TILTON' chain, two jaws rigidly attached to the han- Witnesses: dle, eaeh jaw having a toothed or serrated JACOB I. BERGEN7 edge7 the teeth or serrations of which extend WM. L. MORRIS. 

